1. Technical Field
The present disclosure relates generally to user devices that include optical face detection capabilities.
2. Description of the Related Art
User devices such as smart phones and tablet personal computers (PCs) often include a basic face detection capability enabled using a front optical camera. Image processing can generally detect a face within the focal plane if the person is properly illuminated and positioned. Several algorithms in different applications on user devices benefit from the face detection capability. For example, a phone camera and a single lens reflex (SLR) camera use face detection to determine exposure and to focus on a face, if any, that is within view. Failure to correctly detect a face can thus result in improper focus and an incorrect exposure. Thus, the captured image can be too dark and/or overexposed and/or blurred. However, in a significant number of situations, image processing is unreliable. False positives occur when objects are incorrectly deemed to be a face. False negatives occur when a face is not detected. Errors in face detection tend to occur in dark images, backlit images, and very bright images.